Mod for DVD player Hi-Rez stereo PCM output - SACD DVD-A HDCD

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" ... using it as a digital transport with HDMI digital video and my digital audio output. ..."

I'm connecting to the Oppo 6-port Dolby (analog) output ports, thus using that el cheap-o Oppo internal 24-bit DAC (apparently it is 192K, but can't be sure). I have not even tried the HDMI digital signal path. I assume that your DAC deals with this (unconverted) signal path, rather than the internal Oppo DAC ... Yes?

" ... The stock Oppo power supply caps are too small ..."

Agreed. I added a pair of 450 uF Tantalum caps to the Oppo switching supply circuit board output (one each on +/- 9VDC rails) and another pair of 0.01 uF yellow (MKT?) plastic caps to the connector on the Oppo DAC board at the input connector (one each on +/- 9VDC rails). That's all I have done so far. Suggestions??

" ... The Oppo sends the data from the MediaTek chip to the onboard DAC as 3.3V logic, so I used 3.3V as the VL on the Cirrus Logic resampler chip. ..."

... Meaning you built a completely seperate DAC board and installed this in the Oppo case.

" ... take the standby (always on) 5V and drop it through a diode to about 4.3V. Then I use multiple tantalum caps as charge storage that will keep the oscillators running through power glitches. ..."

I would have assumed that would be much more complicated than cleaning up the available +/- 9 VDC :eek: :confused: ... But if this works better, well ... :>)

" ... didn't buy parts to stuff all 5 boards. Especially the the two Cirrus Logic chips CS8421 ( $9.10 at Digikey 598-1126-5-ND ) and CS8406 ( $5.04 at Digikey 598-1121-5-ND ) I only bought two each of those chips. The rest of the parts are not that expensive. I did buy enough of the low-jitter oscillators for all 5 boards.

" ... I didn't buy parts to stuff all 5 boards. ... New PCBs should be here next week! ..."

Assuming that your capital outlay is under US$100 per unit for parts and labor, but ignoring any considerations for niceities like warranties, I would be more than willing to purchase one of your completed (stuffed and tested) boards, if possible, and I am willing to do so even if they are not totally successful as I believe that the Oppo 981 device, generally, is worthy of experimentation and potential improvement. I'm happy with check, paypal or whatever, in advance, if you feel confident enough to attempt this. (I am handy with a soldering iron, but my 62 year old eyes won't let me do the tiny work anymore ... .) My email address is in my profile :smash:
 
I am extremely interested in this as well. I JUST bought a Denon 3910 II unit, for about $400cdn. I also bought the new EMU 0202 2 channel 24/192 USB 2.0 recorder.

I'm looking to record a bunch of LP's on a $5-10k analog rig, to make DVD-A's or what can be made ..to get a 24/96 output from the Denon..to my DEQX. In this way, I can record at the 24/192....use a good algorthim package to scale back to 24/96..and play the recorded discs at 24/96 off the Denon..and out to the DEQX highly modded crossover.

This is for an audio show ..I gotta figger this out and have it running in less than a month. I can show fine at the 44khz, no problemo, but a bit more rez off a good analog recording is a far better situation.

I've no idea what rate the digital output comes out at on an unprotected self made DVD-A format disc, on the Denon hardware. It is very similar, if not idential to the oppo unit-hardware wise.

I'm curious, from what you say, if I will be limited in resolution. ie, 16/48, max, or similar (16 at 44k).
 
While driving home (between previous post and this one) the thought occurred that what Rossi is really building is a "breakout box" device for extracting the audio component from the HDMI circuit of just about any DVD player that has HDMI output. Granted that some players may have better features than others, but the HDMI data format is supposed to contain all of the digital audio elements of DVD-A, SACD, et al ... See http://en.wikipedia.org/wiki/HDMI ... and ... http://upload.wikimedia.org/wikiped...inout.svg/310px-HDMI_Connector_Pinout.svg.png . Of particular interest here: " ... HDMI also includes support for 8-channel uncompressed digital audio at 192K Htz sample rate with 24 bits/sample as well as any compressed stream such as Dolby Digital, or DTS. ..."

So, Rossi's efforts could (or at least might) be adaptable, generically, to just about any DVD-A / SACD / DVD-Video player with a "standard" HDMI connector that provided sufficient 5 VDC power as per the cabling "standard" and the digital audio "standard".

(HDMI standards are still in flux, some specs have changed since original introduction. "... HDMI Specification 1.0, updated in HDMI 1.2a, and again in 1.3a (Added timer and audio commands). ... With version 1.3, HDMI now also supports very high bit rate lossless compressed streams such as Dolby TrueHD and DTS-HD Master Audio. ..." ? Version 1.4 announced tentatively, at Jan. 2007 CES trade show, apparently upgrades the video [and other?] and there are rumors of version 1.5, changes are TBD = ?)

Thus, maybe this should be a relatively inexpensive, external device rather than building it into a player or a pre-amp ... at least until the "standard" becomes more stable ... 2.0?

Anyway, I would hope that anyone considering something along these lines keep in mind that a) an external device might be more desirable and b) an external power source may be called for as, if HDMI lines are long (1080p cable can be up to 10 meters long) the 5 VDC source & ground on HDMI pin 18 may be quite anemic and c) the actual DAC circuit board might be built on an upgradable sister or daughter board, separate from the HDMI interface board ... No ?? Yes ?? Like this? :
 

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Just thought it was fitting this thread to mention that somebody has started offering mods for OPPO players:

http://www.referenceaudiomods.com/M...ppo_Units&Category_Code=MODS&Product_Count=39

However, the prices seem obscene since the mods in some cases cost several times the entire price of the player itself!!!!

Suppose it has something to do with labour cost in California (where the mods are made) vs. labour cost in China (where the players are made) :D
 
" ... Are you volunteering to demultiplex and decrypt the HDMI datastream ? ..."

Point me to the right chip set and I'll see what can be done. Picking the right combination is the most significant task may be completed ... after that the use of reference designs (board level subassemblies) from the manufacturers may be in order. Then ... we will see ...

Of interest: http://www.gefen.com/kvm/product.jsp?prod_id=3939 ... HDMI video passes on through to DVI connector ... and "breaks out" digital optical audio ... just add a better DAC to this box? ... this one goes the other way: http://www.gefen.com/kvm/product.jsp?prod_id=3570 ...

:smash:
 
KBK said:
I've no idea what rate the digital output comes out at on an unprotected self made DVD-A format disc, on the Denon hardware. It is very similar, if not idential to the oppo unit-hardware wise.

I'm curious, from what you say, if I will be limited in resolution. ie, 16/48, max, or similar (16 at 44k). [/B]

If you author your own DVD-A discs and make them unprotected, the Denon should output at full resolution. The down-rezzing only happens when DRM is applied.
 
FastEddy said:
Of interest: http://www.gefen.com/kvm/product.jsp?prod_id=3939 ... HDMI video passes on through to DVI connector ... and "breaks out" digital optical audio ... just add a better DAC to this box? ...

[/B]

That would work as long as the the Gefen box has a HDMI receiver chip with a revision level of 1.1 or greater. The Oppo will not send hi-rez digital audio if the receiver is only HDMI 1.0

The manual doesn't say.

At $299 it is a little pricey :D
 
FastEddy : "Of interest: http://www.gefen.com/kvm/product.jsp?prod_id=3939 ... HDMI video passes on through to DVI connector ... and "breaks out" digital optical audio ... just add a better DAC to this box? ... "


Rossi: " That would work as long as the the Gefen box has a HDMI receiver chip with a revision level of 1.1 or greater. The Oppo will not send hi-rez digital audio if the receiver is only HDMI 1.0 ... The manual doesn't say. ..." But I am sure you are right, Gefen trying to maintain some level of backward compatibility for marketing reasons ... " At $299 it is a little pricey ..." Yes and so is my collection of DVD-A and SACD discs.

... and thus the real reason for this madness ... this effort to discover a good DIY device that will "capture" that digital audio signal and convert it to the best quality analog audio, possible.

Yes the Gefen device may be pricey, and it still isn't good enough ... :apathic:

Mercinary announcement: I'm a dealer for the Gefen stuff. If there is a reasonable way to build this device, I would subsidize the short run manufacture of it = a profit motive. In any case I do want it for my own system, whether it is Rossi's addin board for the Oppo or a "generic" device that would work with other players ... :smash:
 
rfbrw: " ... I would have thought that would put you in a better position to know what [Gefen] chipsets are available. ..."

Yes, if I took one from stock and opened it up. It is digital "breakout" to digital optical / coaxial audio out ... which still leaves the question of the DAC.

The Gemmun chip set you indicate is also a digital breakout to digital audio, which still leaves the question of a proper DAC. (This Gemmun series is quite interesting. They have the impedence matching questions figured out for use on the end of a longer cable, which is good. Meaning that they are directly addressing the Gefen device and could be the Gefen chip supplier for all I know. They also seem to be a supplier to several other companies making better quality 24 bit DACs, so maybe ... )

Thanks for the tips, I'll get in touch with them ...
 
FastEddy said:
Yes, if I took one from stock and opened it up. It is digital "breakout" to digital optical / coaxial audio out ... which still leaves the question of the DAC.


I would be interested in seeing a good digital picture of the inside. (good enough to read chip labels) also data sheets and schematics if you have them.


The data sheet for the Gefen box says HDCP pass-through, which means you will need a HDCP compliant TV connected to the DVI port before it will allow data to pass. This is a big drawback of this plan.
 
I'll say this: I suppose I could just get one of the Gefen devices and then take a look at making or finding a good DAC, provided the Gefen device actually does pass all of the 24 bit / 192K /Dolby 5.1 out of that port ... then all I need to add is something we carry in stock to pass the HDMI on to the display(s). ( http://industrialcomponent.com/hdavlink/hdvifm.html ... this adapter is used to connect Apple or other computers to any HDMI display ... but it does not pass along the HDMI v. 1.whatever audio = a simple fix).

I guess I'll order up one and open it up. Is HDMI 1.2a good enough? http://en.wikipedia.org/wiki/Hdmi : "[1.3] Supports output of Dolby TrueHD and DTS-HD Master Audio streams for external decoding by AV receivers. ..." I wondered if DTS-HD is worth the chip change? 1.0 and up = "8-channel/192kHz/24-bit audio". (HDMI 1.3 is the Sony PlayStation 3 and a few other gadgets. I have trouble considering the PlayStation as a music server, but ... )

There has to be a way to get the full bloom offa this punkin = get the full 1.3 load outta the Oppo and pass it along as 8-channel/192kHz/24-bit analog audio to a quality playback system.

I guess I'm still wondering how I can get one of your (Rossi's) DAC boards. Internal may be the only way ... but then what about those two other DVD players (a modern Samsung HDMI v. 1.? and an old Marantz) I have and all the other players out there?

....
Mercinary announcement: industrialcomponent.com > That's my company ...
 
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